Reginald P. Smithers III wrote:

One last article from the US govt. on wind chill and radiator freezing:

2. Can windchill impact my car's radiator or exposed water pipe? back

A. The only effect windchill has on inanimate objects, such as car
radiators and water pipes, is to shorten the amount of time for the
object to cool. The inanimate object will not cool below the actual air
temperature. For example, if the temperature outside is -5 degrees
Fahrenheit and the windchill temperature is -31 degrees Fahrenheit, then
your car's radiator will not drop lower than -5 degrees Fahrenheit.

http://www.weather.gov/os/windchill/...glossary.shtml